Automatic controlling system for internal-combustion engines



E. T. LARKIN Sept. 23, 1930.

AUTOMATIC CONTROLLING SYSTEM FOR INTERNAL COMBUSTION ENGINES Filed Dec.27,

a 5: 3 Q A Patented Sept. 23, 1930 UNITED STATES PATENT OFFICE AUTOMATICCONTROLLING SYSTEM FOR INTERNAL-COMBUSTION ENGINES Application filedDecember 27, 1926. Serial No. 157,405.

This invention relates to systems for automatically controlling theoperation of internal combustion engines, and more particularly to thestarting and stopping thereof.

The objects of this invention are to provide a system of this kind bymeans of which an internal combustion engine may be started and stoppedwithout requiring any attention by an operative; also to provide asystem of this kind with a control switch which, when closed, completesthe ignition circuit of the engine, and a relay starting circuit, whichis interrupted when the engine attains a predetermined speed, thecontrol switch when opened stopping the engine by breaking the ignitioncircuit; also to provide a system of this kind of means of'which theignition devices of the engine are controlled automatically so that theignition or spark is retarded during the starting of the engine andadvanced after the engine has been started; also to provide a system ofthis kind by means of which a priming charge of fuel is supplied to theengine during the starting thereof; also to provide a system of thiskind in which the operation of the starting motor of the engine isautomatically stopped when the engine attains a predetermined speed;also to provide a system of this kind in which the operation of thestarting motor is interm ttent; also to provide a system of this kind inwhich the starting motor circuit is interrupted after the engine hasbeen started; also to provide a system of this kind with control devicesof improved construction for effecting the retarding of the ignitionspark before the starting motor circuit is closed; also to provide asystem of this kind which is capable of being operated at a distanceremote from the engine itself; also to provide a system of this kind bymeans of which the supply of fuel to the engine is automaticallymaintained during the starting and operation of the engine andinterrupted when the engine is stopped; also to improve systems of thiskind in other respects hereinafter specified.

The single figure of the accon- 'ianying drawing shows diagrammaticallya system embodying my invention for automatically controlling theoperation of internal combustion engines.

ln many instances where fans, blowers, pumps, machines or other devicesare driven by electric motors or other sources of power, it isfrequently desirable to have an independent auxiliary driving unit, suchas an internal combustion engine, which can be operated in case the maindriving unit ceases to operate or becomes overloaded and it isfrequently desirable to have the auxiliary source of power placed intooperation immediately upon the arising of the necessity therefor. Forexample in mine ventilation, fans or blowers may be operated by electricmotors and if for any reason the supply of power to the electric motorbecomes interrupted it is necessary that an auxiliary source of power beimmediately placed into opera tion, and the system shown in the drawingsis intended to render an internal combustion engine usable as anauxiliary source of power in instances of this kind. It will beunderstood, however, that it is not intended to limit this invention foruse in connection with operating blowers since thesystcm may be employedin any other instance Where it is desired to automatically start andstop an internal combustion engine, and the system may also be manuallyoperated in such a manner that the mere closing of a switch causes theautomatic starting of an internal combustion engine.

In the accompanying drawing, A represents a control switch which may beactuated either manually or automatically in any suitable manner toclose a series of circuits, the switch shown including a conductor awhich is adapted to connect a pair of fixed contacts or terminals 4 and5, a conductor a which completes a circuit between two con tacts orterminals 6 and 7 when the switch is closed, and a conductor a whichfunctions in a similar manner in connection with two contacts orterminals 8 and 9. The drawing illustrates by way of example one mannerin which the switch A may be actuated automatically, namely by means ofa solenoid B having a core b connected with the movable member A of theswitch. In case the system contacts with the terminals 4:, 5, 6, 7, 8and 9.

This means for actuating the switch member A is merely shown toillustrate one embodiment of this invention and it will be obvious thatthe switch member B may be actuated by means of a thermostatic device, afloat device, or any other control means.

The contacts 6 and 7 are connected respectively with conductors l0 and11, which conductors are adapted to open a fuel supply valve when theterminals 6 and 7 are connected. For this purpose in the constructionshown a solenoid 12 is provided with which the conductor 10 isconnected, the core of the solenoid being connected to a fuel supplyvalve 13 in such a way that when the current is flowing through thesolenoid 12, the -valve 13 is open to supply fuel to the engine. Theother conductor 11 connects with a conductor 14 leading from a batteryor other source of power C, and the other end of the solenoid 12 isconnected to a conductor 15 leading to another conductor 16 connectedwith the other terminal of the battery C. Any other means for placingthe engine in communication with a supply of fuel may be used, or incases where it is unnecessary to use a valve in the fuel line or wherethe valve can be left open at all times, this circuit may be entirelyomitted from the system.

The control switch A is preferably employed to close the ignitioncircuit of the engine when the control switch is closed, and to breakthe ignition circuit when the switch is open, so that the opening oftheswitch causes the engine to stop. In the construction shown for thispurpose the terminal 4 is connected with a conductor 18 which leads tothe engine ignition system which is not shown in the drawings for thereason that any suitable ignition system may be used for this purpose,the ignition switch being preferably operated from a battery D, saidignition being grounded. The internal combustion engine may be of anysuitable or desired construction and is not shown in the drawings sinceit is of itself no part of this invention, and the variousinstrumentalities used for starting the engine may also be of well knownconstruction and are merely diagrammatically indicated on the drawing.

The terminal 5 connects with a conductor 19 which in turn connects witha conductor 20 leading to the positive terminal of the battery D, theother terminal being rounded. Consequently current from the battery I)flows through the conductors 20 and 19 to the terminal 5 and when thecontrol switch A is closed current flows through the part a of thecontrol switch to the terminal +1 and conductor 18 to the ignitionsystem and then through the ground to the negative terminal of thebattery 1). This circuit remains energized as long as the control switchA remains closed so that when this switch is again opened, for example,by the resumption of the flow of current through the relay B, the engineis immediately stopped by the breaking of the ignition circuit, and theopening of the control switch A will also cause the solenoid 12 to bedeenergized so that the fuel valve 13 is closed by any suitable means,not shown.

The remaining steps leading to the automatic starting of the engine arecontrolled by means of a relay circuit connected with the terminals 8and 9 of the control switch, and preferably though not necessarily,through a relay master switch E, and this circuit is adapted to beinterrupted when the engine has attained a speed somewhat greater thanthat at which it may be turned over by its starting motor. For thispurpose a conductor 201 connects the terminal S) with one end of asolenoid 21 of the master switch E, the other terminal of the solenoid21 being connected by means of a conductor 22 to the conductor 16leading to the positive terminal of the battery C. The other terminal 8of the control switch is connected by means of a conductor 24 to acontact 25 of a suitable switch actuated by means responsive to thespeed of the engine. such as a governor controlled switch E which isdiagrammatically illustrated to include a governor 26 which moves thecontact or switch terminal 25 out of engagement with a fixed contact orterminal 27 after the engine to which the gov ernor is connected reachesa predetermined speed. The stationary contact 27 of the governor switchis connected by means of conductors 28 to a conductor lat which leads tothe negative terminal of the battery C. Consequently the master switch Ewill only be closed when the engine is standing still or operating at alow speed, and as soon as the engine attains a speed somewhat beyondthat at which it can be turned over by the starting motor. the circuitthrough the master switch is broken by means of the governor controlswitch. Consequently the starting devices, which are all actuated bythis relay circuit will be no longer required after the engine has beenstarted and are consequently rendered inoperative by the breaking ofthis relay circuit by the governor controlled switch E. a

The master switch E, in the form shown in the drawing, includes amovable switch member 30 which is connected to a core 31, the movablemember 30, when the solenoid 21 is energized, being in its upperposition in contact with switch terminals 32, 33, 34 and 35. Other meansfor interrupting the flow of current to the relay circuit connected withthe terminals 8 and 9 of the control switch when the engine has beenstarted may be employed if desired.

The closing of the relay circuit effects the intermittent operation ofone or more switches or relays for intermittently actuatingseveraldevices used for starting the engine. In the particularconstruction shown for this purpose, the negative terminal of thebattery C is connected through conductor 14 and a conductor 37 to thecontact 34, and when the master switch E is closed current flows fromthe contact 34 through a part of the master switch to the terminal orcontact 35 and thence through a conductor 38 to the fixed terminal orcontact 39 of an intermittently operating relay switch, the movablecontact 40 of this switch being intermittently opened and closed by anysuitable means. In the particular construction illustrated, a retardedrelay in the form of a solenoid and dash pot is employed for producingthe intermittent opening and closing of this switch, a solenoid 41having one terminal connected with the movable switch member 40 and theother terminal connected through a conductor 42 and conductor 16 to thebattery C. The solenoid 41 has a core 44 provided at its lower end witha plunger which operates in a dash pot 45 of any usual or suitableconstruction. Consequently when the movable switch member 40 contactswith the fixed terminal or switch member 39, current will flow throughthe solenoid 41 drawing the core 44 upwardly against the action of thedash pot, so that the upward movement of the core will be comparativelyslow. When the flow of current through the solenoid 41 is interrupted,the core 44 and plunger connected therewith will move in the oppositedirection in the dash pot until they reach the lower limit of travel.The reciprocatory movement of the core 44 may be communicated to themovable switch member 40 in any suitable or desired manner. In theparticular construction shown the movable switch member 40 is connectedwith the core 44 of the solenoid by means of a spring 46 which movespast the pivotal axis of the movable switch member 40 during' themovement of the core 44 of the solenoid. When the spring 46 is below thepivotal axis of the movable switch member as shown in the drawings, thespring will tend to swing the movable switch member into its circuitclosing position. WVhen on the other hand the core 44 of the solenoid israised so that the spring 46 swings above the pivot of the movableswitch member 40, the spring 46 will exert an upward pull on the movableswitch member and move the same into its open circuit position asindicated in dotted lines on the drawings.

Other movable switch members may be actuated by the same core 44 of thesolenoid, one such member 49 being shown in the drawings. This movableswitch member 49 is also connected with the core of the solenoid bymeans of a spring 50 and the movable switch member 49 is adapted toengage with a fixed contact or terminal 51. The movable switch member 49operates differently from the mov able switch member 40 in that thedownward movement of the core 44 of the solenoid causes this switchmember 49 to be opened while the upward movement of the core closes theswitch.

The alternate opening and closing of the movable switchmember 49 maycontrol the intermittent supply of current to a part of the startingmechanism of the engine, and in the particular construction shown thisintermittent current is employed to operate a plunger or piston F of aprimer pump, the primer pump being of a reciprocatory type and not beingshown in the drawings. The plunger of piston F is connected with a core54 of a solenoid 55. Current for actuating the solenoid 55 passesthrough a circuit including the conductor 14 and a conductor 56connected with the movable switch member 49, and a conductor 57connecting the fixed switch member or contact 51 with a terminal of thesolenoid 55, the other terminal of the solenoid being connected with aconductor 58 leading to the positive terminal of the battery. The supplyof current to the solenoid 55 causes the plunger F of the primer pump toreciprocate in one direction and when the current in the solenoid isinterrupted, the plunger is returned to its original position. Thisreciprocation of the plunger supplies fuel directly to the intakemanifold of the engine or to any other part thereof where it can bereadily vaporized to hasten the starting of the engine. Since thereciprocatory movement of the core 44 of the solenoid is controlledthrough the relay circuit including the master switch E it will beobvious that when this relay circuit is: opened due to the fact that theengine has attained the necessary speed to actuate the governor switchE, the core 44 of the solenoid will fall by gravity into the positionshown in the full lines in the drawings, in which position the movableswitch member 49 is out of engagement with the terminal or contact 51 sothat the primer pump will then be no longer in operation.

The other steps in the starting of the internal combustion engine areeffected by another intermittently operating switch. which in theparticular construction illustrated is controlled from a separatesolenoid 60 cooperating with the dash pot 61, this solenoid being alsoconnected by means of the conductor 42 and the conductor 16 to thepositive terminal of the battery 0. The other terminal of the solenoid60 is connected through a movable switch member 62, a fixed terminal orcontact 63, and conductor 64, to the fixed contact 32 of the masterswitch E, and consequently when the master switch is closed current willflow through the sole noid 60 through a circuit including the conductors14 and 37 and stationary switch con-' tacts 33 and 32 of the masterswitch E. The solenoid 60 controls the intermittent opening and closingof a switch including a movable switch member 66 cooperating with afixed switch memberjor contact 67 and actuated by means of a spring 68connected with the core of the solenoid 60 in the same manner asdescribed in connection with the switch actuated by the core 44 of thesolenoid 41. The movable switch member 66 connected to one of theterminals of the battery C, for example, the negative terminal by meansof conductors 70, 56 and 14, and the fixed contact or terminal 67 of theswitch is connected by means of a conductor 71 to a solenoid 72 or otherdevice for alternately closing the starting circuit of the startingmotor *of theengine and also operating the spark and throttle control ofthe engine. The other terminal of the solenoid 72 is connected by meansof the conductor 58 to the positive terminal of the battery C. Thesolenoid 72 has a core 74 which is connected to one arm of an enginecontrol lever G which may control the advancing and retarding of theignition spark or the throttle valve of the engine or both of theseinst-rumentalities. In the particular construction shown this enginecontrol lever is pivoted at 7 5 and the other arm 76 of the lever isnormally pulled against the action of the solenoid 7 2 by a coil spring77 or other suitable means, into a position which this engine controllever occupies during the normal operation of the engine. Consequentlythe energizing of the solenoid 72 will cause the core 74 to be drawn ina direction to swing the lever G about-its pivot 7 5 against the actionof the spring 77 into the dotted line position shown in the draw ings,in which position the spark will be retarded for starting and thethrottle will be in a position to facilitate starting of the engine.

In the particular construction shown the energizing of the solenoid 72is also intended to effect the starting of the starting motor of theengine and this may be done in any suitable or desired manner. As shownin the drawings the combined spark control and throttle lever G isconnected to a movable switch member 7 9 by means of a link 80, themovable switch member 79 being grounded as indicated and being normallyheld in an open position shown 1n full lines on the drawing by means ofthe spring 77. The energizing of the solenoid 72, however, causes themovable switch member 79 to be moved into a position in which it makescontact with a fixed switch member or terminal 81 connected by means ofa conductor 82 with a solenoid 83 of a starting switch 84, the otherterminal of the solenoid 83 being connected by means of conductors 85and 20 to the positive terminal of the starting battery D. The closingof the starting switch 84 causes current to flow from the positiveterminal of the starting battery D through conductor 20 and the startingswitch 84 to the starting motor H of the engine, the other terminal ofthe 'motor being connected to the negative ter-- minal of the battery bymeans of a conductor 86 and is grounded at 87. Consequently the closingof the movable switch member 66 intermittently causes an intermittentenergizing of the solenoid 72 so that the starting motor of the engineis operated at intervals and at the same time the spark is retarded andthe throttle lever placed in a position for starting. The intermittentoperation of the starting motor prevents over- .heating of this motor incase the engine is difiicult to start. When the engine is started andattains a speed slightly be 0nd that which the starting motor is capableof imparting to the engine, the governor switch 27 causes the masterswitch E to open so that the switch member 66 will also be moved to itsopen position and thus interrupt the operation of the starting motor aswell as permit the spark to be advanced and the throttle lever to bemoved to its running position. It will be understood that the startingmotor is connected with the engine in the usual manner, by means ofautomatically engaging gears or a ratchet device (not shown).

If desired, the system may also be provided with an alarm device whichis to be actuated when the engine is being started. This may easily beeflected by means of a solenoid operated switch I which closes a circuitincluding an alarm device K. In the particular construction shown thesolenoid switch I is actuated by means of a solenoid 88 connected inparallel with the solenoid 21 of the master switch E so that the alarmdevice will be actuated as long as the engine is being started. As soon,however, as the engine has been started and is in operation, thegovernor controlled switch E will cause the flow of current to solenoids21 and 88 to be interrupted and thus discontinue the actuation of thealarm K. Any other alarm circuit may be used in connection with thestarting system or the alarm device may be entirely eliminated, ifdesired.

Whenever conditions are restored to normill, 'for example by restoringthe flow of current to the control solenoid B, the switch A will bereturned to its normal or open position, thus causing the opening of theignition circuit of the internal combustion engine by opening thecircuit between the terminals 4 and 5, and shutting oil' of the gasolinevalve by opening the circuit between the terminals 6 and 7, so that theoperation of the internal combustion engine is automatically stopped.

It will be understood that the master switch E may be eliminated in casethe control switch A is located near the engine to be started, in whichcase the two solenoids 41 and 60 and the intermittently operating switchmembers 40 and 62 may be connected in parallel in the relay circuitincluding the fixed terminals 8 and 9 of the control switch and thegovernor switch E. In case the control switch is located at aconsiderable distance from the engine to be started, it is desirable touse a master switch, such, for example, as the switch E described, sincethe amount of current required to actuate the master switch isconsiderably less than that required to actuate the two solenoids 41 and60, so that the line losses may be reduced by using a master switch.

The system described has the advantage in that both the starting andstopping of the internal combustion engine takes place entirelyautomatically. Furthermore the system operates so that the operation ofthe starting motor takes place after the gasoline valve is opened andafter the ignition circuit is completed, due to the fact that aninterval of time is required before the solenoid 60 moves the switchmember 66 into its circuit closing position. Furthermore the closing ofthe circuit through the starting motor can be effected only when thespark control lever G is moved into its retarded position so that damagedue to starting the engine with an advanced spark is positively avoided.By causing the starting motor to operate intermittently the starting ofthe engine can be eilected without danger of overheating the startlngmotor, as might be the case if this motor were operated continuouslyuntil the engine is started. By using a separate battery for actuating anumber of the solenoids or relays, the full flow of current from thestarting motor battery D is available for starting and ignition.

I claim as my invention:

1. In a system for starting an internal combustion engine, thecombination of a starting motor. a starting motor circuit, an ignitioncircuit. a control switch for complcting the ignition circuit of theengine, a device which is placed into operation by said control switchand which first retards the spark of the ignition system and thencomplates a circuit through the starting motor of the engine, meansoperated independently of said switch when the engine has attained apredetermined speed for interrupting the circuit through the startingmotor of the engine, and means actuated by the interrupting of thestarting motor circuit for advancing said spark when the engine isstarted.

2. In a system for automaticallv starting an internal combustion engine,the combination of a starting motor, a starting motor circuit, anignition circuit, a control switch which when closed completes theignition circuit of the engine, a retarded and intermittently operatingrelay energized by the'closing of said control switch for closing saidstarting motor circuit, which circuit is intermittently closed andopened by said relay, and means for interrupting the operation of saidrelay to open the starting motor circuit after the engine has attained apredetermined speed.

3. In a system for starting an internal combustion engine, thecombination of a starting motor, a starting motor circuit, an

ignition circuit, control means for completing the ignition circuit ofthe engine, a retarded relay to which current is supplied when theignition circuit is closed, and a device actuated by said retarded relayand which is connected to impart movements simultaneously to an engineoperating lever and to a switch for completing the circuit through thestarting motor.

4. In a system for starting an internal combustion engine, thecombination of a starting motor, a starting motor circuit, an ignitioncircuit, control means for completing the ignition circuit of theengine, a re tarded relay to which current is supplied when the ignitioncircuit is closed, a solenoid having a movable core, an engine controllever connected with the core so as to be moved into an engine startingposition when the core is drawn into the solenoid, a switch for closingsaid circuit through the starting motor, and a connection between saidlever and said switch to cause the switch to be closed after the leverhas been moved into its starting position.

5. In a system for starting an internal combustion engine, thecombination of a starting motor, a starting motor circuit, an ignitioncircuit, meansfor completing the ignition circuit of the engine, aretarded relay to which current is supplied when the ignition circuit isclosed, a solenoid having a movable core, an engine control leverconnected with the core so as to be moved into an engine startingposition when the core is drawn'into the solenoid, a switch for closingthe circuit through the starting motor, a connection between said leverand said switch to cause the switch to be closed after the lever has benmoved into its starting position, and a device responsive to the speedof the engine and which breaks the circuit to said retarded relay whenthe engine has attained a predetermined speed.

6. In an ignition system for an internal combustion engine. thecombination of a starting motor, a starting motor circuit, an ignitioncircuit, a control switch which when closedlcomplctes said ignitioncircuit, a relay circuit completed by the closing of said controlswitch, a priming device for supplying fuel to the engine which isactuated by. the closing of said relay circuit, an engine control leveryieldingly held in a position which it should occupy when the engine isrunning, a device for moving said engine control lever into a startingposition and closing the circuit through the starting motor of theengine and actuated when said relay circuit is closed, and meansactuated when the engine reaches a predetermined speed for opening saidrelay circuit and thereby permitting said engine control lever to moveto its running position and said starting motor circuit to be opened.

7. In a system for automatically starting an internal combustion engine,the combination of a starting motor, an ignition circuit, a controlswitch which when closed completes the ignition circuit of the engine, amaster switch which is closed by the closing of said control switch, acircuit including a retarded relay which is closed when said masterswitch is closed, a circuit closed by said retarded relay for supplyingcurrent to said starting motor, an engine control lever yieldingly heldin a position which it should 0ccupy when the engine is running, adevice actuated by the circuit of said retarded relay for moving saidcontrol lever into a starting position, and means which operate when theengine has attained a predetermined minimum speed for opening saidmaster switch.

8. In a system for automatically starting an internal combustion engine,the combination of a starting motor, an ignition circuit, a controlswitch which when closed completes the ignition circuit of the engine, apair of retarded relays energized by the closing of said control switch,a starting motor circuit which is closed by one of said retarded relaysafter said ignition circuit is closed, a priming device actuated bymeans of a circuit closed by said other retarded relay. and means forinterrupting the operation of said retarded relays after the engine hasattained a predetermined speed.

9. In a system for automatically starting an internal combustion engine,the combination of a starting motor, an ignition circuit, a controlswitch which when closed completes the ignition circuit of the engine, amaster switch which is closed by the closing of said control switch, apair of circuits closed by said master switch and each including aretarded relay, a circuit including said starting motor which is closedby one of said retarded relays, a circuit including means for actuatinga priming device, which circuit is closed by said other retarded relay,and means for opening said master switch after the engine has beenstarted.

10. In a starting system for an internal combustion engine, thecombination of a starting motor, a starting motor circuit, an ignitioncircuit, a control switch for completing a circuit through the ignitioncircuit of the engine, means actuated by said control switch forautomatically and intermittently supplying current to the startingmotor, and means operating independently of said control switch forstopping the starting motor when the engine has attained a predeterminedspeed.

ELWOOD 'I LARKIN.

